Determining and modeling the response of piezoresistance transducers to dynamic loading

The work of the past year has concentrated on experimental measurements and their analyses. The response of Ytterbium (Yb) foils, oriented parallel and perpendicular to the shock front, was obtained for well defined loading and unloading. The foils were embedded in a PMMA matrix and the longitudinal stress ranged between 0.1 and 2.0 GPa. Results have provided an empirical calibration for Yb under shock wave uniaxial strain loading. An important result from these experiments is the verification of an elastic-plastic inclusion analysis. The results of the 1.9 GPa experiment suggest that under certain conditions a dynamic inclusion analysis will be necessary. Another important aspect of this year's effort was the development of an experimental method to perform low strain-rate tensile experiments on gauge foils.